June 25, 2009, 7:12 PM CT

Demand for food, energy demand to outpace production

With the caloric needs of the planet expected to soar by 50 percent in the next 40 years, planning and investment in global agriculture will become critically important, according a new report released recently (June 25).

The report, produced by Deutsche Bank, one of the world's leading global investment banks, in collaboration with the University of Wisconsin-Madison's Nelson Institute for Environmental Studies, provides a framework for investing in sustainable agriculture against a backdrop of massive population growth and escalating demands for food, fiber and fuel.

"We are at a crossroads in terms of our investments in agriculture and what we will need to do to feed the world population by 2050," says David Zaks, a co-author of the report and a researcher at the Nelson Institute's Center for Sustainability and the Global Environment.

By 2050, world population is expected to exceed 9 billion people, up from 6.5 billion today. Already, as per the report, a gap is emerging between agricultural production and demand, and the disconnect is expected to be amplified by climate change, increasing demand for biofuels, and a growing scarcity of water.

"There will come a point in time when we will have difficulties feeding world population," says Zaks, a graduate student whose research focuses on the patterns, trends and processes of global agriculture......... Posted by: Tyler      Read more         Source

June 21, 2009, 8:40 PM CT

In a Geologic Instant

Modern glaciers, such as those making up the Greenland and Antarctic ice sheets, are capable of undergoing periods of rapid shrinkage or retreat, as per new findings by paleoclimatologists at the University at Buffalo.

The paper, published on June 21 in Nature Geoscience, describes fieldwork demonstrating that a prehistoric glacier in the Canadian Arctic rapidly retreated in just a few hundred years.

The proof of such rapid retreat of ice sheets provides one of the few explicit confirmations that this phenomenon occurs.

Should the same conditions recur today, which the UB researchers say is very possible, they would result in sharply rising global sea levels, which would threaten coastal populations.

"A lot of glaciers in Antarctica and Greenland are characteristic of the one we studied in the Canadian Arctic," said Jason Briner, Ph.D., assistant professor of geology in the UB College of Arts and Sciences and main author on the paper. "Based on our findings, they, too, could retreat in a geologic instant."

The new findings will allow researchers to more accurately predict how global warming will affect ice sheets and the potential for rising sea levels in the future, by developing more robust climate and ice sheet models.

Briner said the findings are particularly relevant to the Jakobshavn Isbrae, Greenland's largest and fastest moving tidewater glacier, which is retreating under conditions similar to those he studied in the Canadian Arctic......... Posted by: Tyler      Read more         Source

June 16, 2009, 9:44 PM CT

Climate change is already having an impact

Extreme weather, drought, heavy rainfall and increasing temperatures are a fact of life in a number of parts of the U.S. as a result of human-induced climate change, scientists report today in a new evaluation. These and other changes will continue and likely increase in intensity into the future, the researchers found.

Scientists representing 13 U.S. government science agencies, major universities and research institutes produced the study, "Global Climate Change Impacts in the United States." Commissioned in 2007, it is the most comprehensive report to date on national climate change, offering the latest information on rising temperatures, heavy downpours, extreme weather, sea level changes and other results of climate change in the U.S.

The 190-page report is a product of the interagency U.S. Global Change Research Program, led by the National Oceanic and Atmospheric Administration. It is written in accessible language, intended to better inform members of the public and policymakers about the social, environmental and economic costs of climate change. It focuses on effects by region and details how the nation's transportation, agriculture, health, water and energy sectors will be affected in the future.

In a press conference today, University of Illinois Harry E. Preble Professor of Atmospheric Sciences Don Wuebbles, a contributor to the evaluation, outlined the current and predicted effects of climate change in the Midwest U.S......... Posted by: Tyler      Read more         Source

June 10, 2009, 9:43 PM CT

A new measure of global warming from carbon emissions

Damon Matthews, a professor in Concordia University's Department of Geography, Planning and the Environment has found a direct relationship between carbon dioxide emissions and global warming. Matthews, together with colleagues from Victoria and the U.K., used a combination of global climate models and historical climate data to show that there is a simple linear relationship between total cumulative emissions and global temperature change. These findings would be reported in the next edition of Nature, to be released on June 11, 2009.

Until now, it has been difficult to estimate how much climate will warm in response to a given carbon dioxide emissions scenario because of the complex interactions between human emissions, carbon sinks, atmospheric concentrations and temperature change. Matthews and his colleagues show that despite these uncertainties, each emission of carbon dioxide results in the same global temperature increase, regardless of when or over what period of time the emission occurs.

These findings mean that we can now say: if you emit that tonne of carbon dioxide, it will lead to 0.0000000000015 degrees of global temperature change. If we want to restrict global warming to no more than 2 degrees, we must restrict total carbon emissions from now until forever to little more than half a trillion tonnes of carbon, or about as much again as we have emitted since the beginning of the industrial revolution......... Posted by: Tyler      Read more         Source

June 10, 2009, 8:42 PM CT

Maybe it's raining less than we thought

It's conventional wisdom in atmospheric science circles: large raindrops fall faster than smaller drops, because they're bigger and heavier. And no raindrop can fall faster than its "terminal speed"its speed when the downward force of gravity is exactly the same as the upward air resistance.

Now two physicists from Michigan Technological University and his colleagues at the Universidad Nacional Autnoma de Mxico (National University of Mexico) have discovered that it ain't necessarily so.

Some smaller raindrops can fall faster than bigger ones. In fact, they can fall faster than their terminal speed. In other words, they can fall faster than drops that size and weight are supposed to be able to fall.

And that could mean that the weatherman has been overestimating how much it rains.

The findings of Michigan Tech physics professors Alexander Kostinski and Raymond Shawco-authors with Guillermo Montero-Martinez and Fernando Garcia-Garcia on a paper scheduled for publication online June 13, 2009, in the American Geophysical Union's journal Geophysical Research Letterscould improve the accuracy of weather measurement and prediction.

The scientists gathered data during natural rainfalls at the Mexico City campus of the National University of Mexico. They studied approximately 64,000 raindrops over three years, using optical array spectrometer probes and a particle analysis and collecting system. They also modified an algorithm or computational formula to analyze the raindrop sizes......... Posted by: Tyler      Read more         Source

Fri, 05 Jun 2009 02:50:50 GMT

Glass Bottles for an Eco-Friendly Spa Table

Bring the spa look home with an eco-friendly spin. Crate and Barrel has some nifty Glass Beverage Bottles that are inspired by their plastic counterparts. Available in a small and large size, the clear glass bottles come with silicone stoppers.

How cool would it be to dress up the table with these? Prices start at $7.95 for the small one. Posted by: Editor      Read more     Source

June 1, 2009, 4:58 AM CT

Population responses to climate change

Biologists have for several years modeled how different species are likely to respond to climate change. Most such studies ignore differences between populations within a species and the interactions between species, in the interest of simplicity. An article in the recent issue of BioScience, by Eric Post of Pennsylvania State University and five colleagues, shows how these limitations can be avoided. Their approach, which relies on multi-stage analyses of how populations fluctuate over time, could allow biologists to model responses to climate change with improved accuracy. In particular, the approach could help identify regions where local populations are vulnerable to climate change, and it could elucidate species interactions that may not be obvious.

The article concentrates on recent analyses by Post and others of yellow-billed cuckoos, caribou/wild reindeer, elk and red deer, and wolves and moose. Continent-wide and hemisphere-wide responses depended both on local weather and on broader climate patterns, and all species showed marked variation among populations. The pattern of responses, Post and his colleagues report, "suggests a strong role for species interactions in buffering responses to climate." For example, local populations near the northern edge of a species' range often seem to be more directly affected by climate than do populations near the southern edge, where biological interactions typically complicate responses to climate change......... Posted by: Tyler      Read more         Source

June 1, 2009, 4:57 AM CT

Who will pick up the bill?

Ocean acidification, a direct result of increased CO2 emission, is set to change the Earth's marine ecosystems forever and may have a direct impact on our economy, resulting in substantial revenue declines and job losses.

Intensive fossil-fuel burning and deforestation over the last two centuries have increased atmospheric CO2 levels by almost 40%, which has in turn fundamentally altered ocean chemistry by acidifying surface waters. Fish levels and other sea organisms such as planktons, crabs, lobsters, shrimp and corals are expected to suffer, which could leave fishing communities at the brink of economic disaster.

Published recently, Monday, 1 June, in IOP Publishing's Environmental Research Letters, the paper 'Anticipating ocean acidification's economic consequences on commercial fisheries' suggests a series of measures to manage the impact that declining fishing harvests and revenue loss will have on a wide range of businesses from commercial fishing to wholesale, retail and restaurants.

Ocean acidification and declining carbonate ion concentration in sea water could directly damage corals and mollusks which all depend on sufficient carbonate levels to form shells successfully. Subsequent losses of prey such as plankton and shellfish would also alter food webs and intensify competition among predators for nourishment......... Posted by: Tyler      Read more         Source

May 28, 2009, 5:19 AM CT

Sea-level rise may pose greatest threat

The melting of the Greenland Ice Sheet this century may drive more water than previously thought toward the already threatened coastlines of New York, Boston, Halifax and other cities in the northeastern United States and Canada, as per new research.

Results of the study are being published this week in Geophysical Research Letters They suggest that moderate to high rates of ice melt from Greenland may shift ocean circulation by about 2100, causing sea levels off the northeast coast of North America to rise by about 30 to 51 centimeters (12 to 20 inches) more than other coastal areas.

The research builds on recent reports that have observed that sea level rise could adversely affect North America, and its findings suggest that the situation is even more urgent than previously believed.

"If the Greenland melt continues to accelerate, we could see significant impacts this century on the northeast U.S. coast from the resulting sea level rise," says scientist Aixue Hu, the paper's main author. Hu is at the National Center for Atmospheric Research (NCAR) in Boulder, Colo. "Major northeastern cities are directly in the path of the greatest rise".

A study in Nature Geoscience in March warned that warmer water temperatures could shift ocean currents in a way that would raise sea levels off the Northeast by about eight inches more than the average global sea level rise that is expected with global warming......... Posted by: Tyler      Read more         Source

May 20, 2009, 5:12 AM CT

Global warming could be double previous estimates

The most comprehensive modeling yet carried out on the likelihood of how much hotter the Earth's climate will get in this century shows that without rapid and massive action, the problem will be about twice as severe as previously estimated six years ago - and could be even worse than that.

The study uses the MIT Integrated Global Systems Model, a detailed computer simulation of global economic activity and climate processes that has been developed and refined by the Joint Program on the Science and Policy of Global Change since the early part of 1990s. The new research involved 400 runs of the model with each run using slight variations in input parameters, selected so that each run has about an equal probability of being correct based on present observations and knowledge. Other research groups have estimated the probabilities of various outcomes, based on variations in the physical response of the climate system itself. But the MIT model is the only one that interactively includes detailed therapy of possible changes in human activities as well - such as the degree of economic growth, with its associated energy use, in different countries.

Co-author of study Ronald Prinn, the co-director of the Joint Program and director of MIT's Center for Global Change Science, says that, regarding global warming, it is important "to base our opinions and policies on the peer-evaluated science," he says. And in the peer-evaluated literature, the MIT model, unlike any other, looks in great detail at the effects of economic activity coupled with the effects of atmospheric, oceanic and biological systems. "In that sense, our work is unique," he says......... Posted by: Tyler      Read more         Source

May 19, 2009, 5:29 AM CT

Concrete's Carbon Footprint

A number of researchers currently think at least 5 percent of humanity's carbon footprint comes from the concrete industry, both from energy use and the carbon dioxide (CO2) byproduct from the production of cement, one of concrete's principal components.

Yet several studies have shown that small quantities of CO2 later reabsorb into concrete, even decades after it is emplaced, when elements of the material combine with CO2 to form calcite.

A study appearing in the June 2009 Journal of Environmental Engineering suggests that the re-absorption may extend to products beyond calcite, increasing the total CO2 removed from the atmosphere and lowering concrete's overall carbon footprint.

While preliminary, the research by civil and environmental engineering professor Liv Haselbach of Washington State University re-emphasizes findings first observed nearly half a century ago--that carbon-based chemical compounds may form in concrete in addition to the mineral calcite-now in the light of current efforts to stem global warming.

"Even though these chemical species may equate to only five percent of the CO2 byproduct from cement production, when summed globally they become significant," said Haselbach. "Concrete is the most-used building material in the world"......... Posted by: Tyler      Read more         Source

May 18, 2009, 5:27 AM CT

Biological particles in high-altitude clouds

A team of atmospheric chemists has moved closer to what's considered the "holy grail" of climate change science: the first-ever direct detections of biological particles within ice clouds.

The team, led by Kimberly Prather and Kerri Pratt of the University of California at San Diego, Scripps Institution of Oceanography, sampled water droplet and ice crystal residues at high speeds while flying through clouds in the skies over Wyoming.

Analysis of the ice crystals revealed that the particles that started their growth were made up almost entirely of either dust or biological material such as bacteria, fungal spores and plant material.

While it has long been known that microorganisms become airborne and travel great distances, this study is the first to yield direct data on how they work to influence cloud formation.

Results of the Ice in Clouds Experiment - Layer Clouds (ICE-L), funded by the National Science Foundation (NSF), appear May 17 in the advance online edition of the journal Nature Geoscience

"If we understand the sources of the particles that nucleate clouds, and their relative abundance, we can determine their impact on climate," said Pratt, main author of the paper.

The effects of tiny airborne particles called aerosols on cloud formation have been some of the most difficult aspects of weather and climate for researchers to understand......... Posted by: Tyler      Read more         Source

May 14, 2009, 9:48 PM CT

Climate Change And Lake Baikal's Unique Biota

Siberia's Lake Baikal, the world's largest and most biologically diverse lake, faces the prospect of severe ecological disruption as a result of climate change, as per an analysis by a joint US-Russian team in the recent issue of BioScience. The lake is considered a treasure trove for biologists and was designated a World Heritage Site by UNESCO because a high proportion of its rich fauna and flora are found nowhere else. Perhaps the most alarming imminent threat stems from the dependence of the lake's food web on large, endemic diatoms, which are uniquely vulnerable to expected reductions in the length of time the lake is frozen each winter.

The article was written by Marianne V. Moore, of Wellesley College in Massachusetts, and five coauthors, including four from Irkutsk State University in Russia. Moore and his colleagues note that Lake Baikal's climate has become measurably milder over recent decades, and that annual precipitation is expected to increase. The average ice depth in the lake is known to have decreased in recent decades, and the ice-free season to have increased. Changes in the lake's food-web composition have been documented.

Future shortening in the duration of ice cover is expected to curtail the growth of the lake's endemic diatoms, because unlike most diatoms, they bloom under the ice in springtime and are highly dependent on ice cover for their reproduction and growth. The diatoms constitute the principal food of tiny crustaceans abundant in the lake, and these are in turn preyed upon by the lake's fish. Moreover, the crustaceans could be affected by changes in the transparency of the ice, an expected result of shifting precipitation patterns and changes in wind dynamics......... Posted by: Tyler      Read more         Source

May 14, 2009, 9:32 PM CT

What Caused Earth's Earliest Ice Age?

An international team of geologists may have uncovered the answer to an age-old question - an ice-age-old question, that is. It appears that Earth's earliest ice age may have been due to the rise of oxygen in Earth's atmosphere, which consumed atmospheric greenhouse gases and chilled the earth.

Researchers from the University of Maryland, including post-doctoral fellows Boswell Wing and Sang-Tae Kim, graduate student Margaret Baker, and professors Alan J. Kaufman and James Farquhar, along with colleagues in Gera number of, South Africa, Canada and the United States, uncovered evidence that the oxygenation of Earth's atmosphere - generally known as the Great Oxygenation Event - coincided with the first widespread ice age on the planet.

"We can now put our hands on the rock library that preserves evidence of irreversible atmospheric change," said Kaufman. "This singular event had a profound effect on the climate, and also on life."

Using sulfur isotopes to determine the oxygen content of ~2.3 billion year-old rocks in the Transvaal Supergroup in South Africa, they found evidence of a sudden increase in atmospheric oxygen that broadly coincided with physical evidence of glacial debris, and geochemical evidence of a new world-order for the carbon cycle......... Posted by: Tyler      Read more         Source

May 14, 2009, 5:25 AM CT

Sediments that result from natural petroleum seeps

A newly released study by scientists at Woods Hole Oceanographic Institution (WHOI) and the University of California, Santa Barbara (UCSB) is the first to quantify the amount of oil residue in seafloor sediments that result from natural petroleum seeps off Santa Barbara, California.

The newly released study shows the oil content of sediments is highest closest to the seeps and tails off with distance, creating an oil fallout shadow. It estimates the amount of oil in the sediments down current from the seeps to be the equivalent of approximately 8-80 Exxon Valdez oil spills.

The paper is being reported in the May 15 issue of Environmental Science & Technology.

"Farwell developed and mapped out our plan for collecting sediment samples from the ocean floor," said WHOI marine chemist Chris Reddy, referring to main author Chris Farwell, at the time an undergraduate working with UCSB's Dave Valentine. "After conducting the analysis of the samples, we were able to make some spectacular findings".

There is an oil spill everyday at Coal Oil Point (COP), the natural seeps off Santa Barbara, California, where 20-25 tons of oil have leaked from the seafloor each day for the last several hundred thousand years.

Earlier research by Reddy and Valentine at the site observed that microbes were capable of degrading a significant portion of the oil molecules as they traveled from the reservoir to the ocean bottom and that once the oil floated to sea surface, about 10 percent of the molecules evaporated within minutes......... Posted by: Tyler      Read more         Source

May 12, 2009, 10:12 PM CT

Global warming driving Michigan mammals north

Some Michigan mammal species are rapidly expanding their ranges northward, apparently in response to climate change, a new study shows. In the process, these historically southern species are replacing their northern counterparts.

The finding, by researchers at the University of Michigan, Michigan State University and Ohio's Miami University, appears in the recent issue of the journal Global Change Biology.

"When you read about changes in flora and fauna related to climatic warming, most of what you read is either predictive-they're talking about things that are going to happen in the future-or it's restricted to single species living in extreme or remote environments, like polar bears in the Arctic," said lead author Philip Myers, professor of ecology and evolutionary biology at U-M. "But this study documents things that are happening right now, here at home".

What will be the ultimate impact of Michigan's changing mammal communities?

"We're talking about the commonest mammals there, mammals that have considerable ecological impact," Myers said. "They disperse seeds, they eat seeds, they eat the insects that kill trees, they disperse the fungus that grows in tree roots that is necessary for trees to grow, and they're the prey base for a huge number of carnivorous birds, mammals and snakes. But we don't know enough about their natural history to know whether replacing a northern species with a southern equivalent is going to pass unnoticed or is going to be catastrophic. It could work either way......... Posted by: Tyler      Read more         Source

May 12, 2009, 5:25 AM CT

Green renovations in existing US schools

Going green with new construction is a good idea, but what about renovating existing structures? Like, say, the 20 billion square feet of existing U.S. public schools, 40 percent of which have 15 million students in poor environmental conditions?

These are questions at the heart of research by Ihab M.K. Elzeyadi, a professor of architecture at the University of Oregon. Elzeyadi has completed the first stage of creating a Green Classroom Toolbox for architects and planners to use in their energy retrofits and modernization plans. His second of three presentations in a three-month period will be May 13 during Solar 2009, the 38th national meeting of the American Solar Energy Society, in Buffalo, N.Y.

"We believe our findings can help plan classroom designs and retrofits to green our aging schools, which are energy and environmentally unconscious," said Elzeyadi, who also is a participating faculty member in the Oregon Built Environment & Sustainable Technologies Center (Oregon BEST), an independent, nonprofit organization established by the Oregon Legislature in 2007.

"Under the American Recovery and Reinvestment Act of 2009, school districts will have access to federal funding to modernize and green their schools," he said. "Our work provides school designers and officials with the needed guidelines to direct this process the right way."It will act as a decision support system"......... Posted by: Tyler      Read more         Source

May 12, 2009, 5:22 AM CT

West coast areas most affected by humans

Climate change, fishing, and commercial shipping top the list of threats to the ocean off the West Coast of the United States.

"Every single spot of the ocean along the West Coast," said Ben Halpern, a marine ecologist at the National Center for Ecological Analysis and Synthesis (NCEAS) at the University of California, Santa Barbara, "is affected by 10 to 15 different human activities annually".

In a two-year study to document the way humans are affecting the oceans in this region, Halpern and his colleagues overlaid data on the location and intensity of 25 human-derived sources of ecological stress, including climate change, commercial and recreational fishing, land-based sources of pollution, and ocean-based commercial activities.

With the information, they produced a composite map of the status of West Coast marine ecosystems.

The work was published online today in the journal Conservation Letters, and was conducted at NCEAS. NCEAS is primarily funded by NSF's Division of Environmental Biology.

"This important analysis of the geography and magnitude of land-based stressors should help focus attention on the hot-spots where coordinated management of land and ocean activities is needed," said Phillip Taylor, section head in NSF's Division of Ocean Sciences......... Posted by: Tyler      Read more         Source

May 7, 2009, 10:16 PM CT

Cutting cattle methane

Beef farmers can breathe easier thanks to University of Alberta scientists who have developed a formula to reduce methane gas in cattle.

By developing equations that balance starch, sugar, cellulose, ash, fat and other elements of feed, a Canada-wide team of researchers has given beef producers the tools to lessen the methane gas their cattle produce by as much as 25 per cent.

"That's good news for the environment," said Stephen Moore, a professor of agricultural, food and nutritional science at the University of Alberta in Canada. "Methane is a greenhouse gas, and in Canada, cattle account for 72 per cent of the total emissions. By identifying factors such as diet or genetics that can reduce emissions, we hope to give beef farmers a way to lessen the environmental footprint of their cattle production and methane reductions in the order of 25 per cent are certainly achievable".

Using information from prior studies, the scientists compiled an extensive database of methane production values measured on cattle and were able to formulate equations to predict how much methane a cow would produce based on diet.

The study was jointly conducted with the universities of Guelph and Manitoba, Agriculture and Agri-Food Canada and the International Atomic Energy Agency in Austria. It published recently in the Journal of Animal Science........ Posted by: Tyler      Read more         Source

May 1, 2009, 5:22 AM CT

Glacial Advances

The vast majority of the world's glaciers are retreating as the planet gets warmer. But a few, including glaciers south of the equator in South America and New Zealand, are inching forward.

A paper in this week's issue of the journal Science puts this enigma in perspective; for the last 7,000 years, New Zealand's largest glaciers have often moved out of step with glaciers in the Northern Hemisphere, pointing to strong regional variations in climate.

"This research should provide much more accurate reconstructions of glacial advances worldwide, allowing us in turn to make climate models more accurate," said Paul Filmer, program director in the National Science Foundation's (NSF) Division of Earth Sciences, which funded the research.

Conventional wisdom holds that during the era of human civilization, climate has been relatively stable. The newly released study is the latest to challenge this view, by showing that New Zealand's glaciers have gone through rapid periods of growth and decline during the current interglacial period known as the Holocene.

"New Zealand's mountain glaciers have fluctuated frequently over the last 7,000 years, and glacial advances have become slightly smaller through time," said Joerg Schaefer, main author of the paper and a geochemist at Columbia University's Lamont-Doherty Earth Observatory......... Posted by: Tyler      Read more         Source

April 29, 2009, 5:04 AM CT

'Chevrons' are not evidence of megatsunamis

A persistent school of thought in recent years has held that so-called "chevrons," large U- or V-shaped formations found in some of the world's coastal areas, are evidence of megatsunamis caused by asteroids or comets slamming into the ocean.

University of Washington geologist and tsunami expert Jody Bourgeois has a simple response: Nonsense.

The term "chevron" was introduced to describe large dunes shaped something like the stripes you might see on a soldier's uniform that are hundreds of meters to a kilometer in size and were originally found in Egypt and the Bahamas.

But the discovery of similar forms in Australia and Madagascar led some researchers to theorize that they were, in fact, deposits left by huge tsunami waves, perhaps 10 times larger than the devastating Indian Ocean tsunami of December 2005.

Such huge waves, they suggest, would result from the giant splash of an asteroid or comet hitting the ocean. They also suggest one such impact occurred 4,800 to 5,000 years ago, and that chevrons in Australia and Madagascar point to its location in the Indian Ocean.

But Bourgeois said the theory just doesn't hold water.

For example, she said, there are numerous chevrons on Madagascar, but a number of are parallel to the coastline. Models created by Bourgeois' colleague Robert Weiss show that if they were created by tsunamis they should point in the direction the waves were travelling, mostly perpendicular to the shore......... Posted by: Tyler      Read more         Source

April 24, 2009, 5:10 AM CT

Forest fires and global warming

Fire's potent and pervasive effects on ecosystems and on a number of Earth processes, including climate change, have been underestimated, as per a new report.

"We've estimated that deforestation due to burning by humans is contributing about one-fifth of the human-caused greenhouse effect -- and that percentage could become larger," said co-author Thomas W. Swetnam of The University of Arizona in Tucson.

"It's very clear that fire is a primary catalyst of global climate change," said Swetnam, director of UA's Laboratory of Tree-Ring Research.

"The paper is a call to arms to earth researchers to investigate and better evaluate the role of fire in the Earth system," he said.

The team also reports that all fires combined release an amount of carbon dioxide into the atmosphere equal to 50 percent of that coming from the combustion of fossil fuels.

"Fires are obviously a main responses to climate change, but fires are not only a response -- they feed back to warming, which feeds more fires," Swetnam said.

When vegetation burns, the resulting release of stored carbon increases global warming. The more fires, the more carbon dioxide released, the more warming -- and the more warming, the more fires.

The very fine soot, known as black carbon, that is released into the atmosphere by fires also contributes to warming......... Posted by: Tyler      Read more         Source

April 22, 2009, 10:13 PM CT

Plants could override climate change effects on wildfires

Scientists predict that global climate change will make many regions around the world warmer and drier, a factor which, taken by itself, would seem to increase the risk of wildfires.

But a new study led by a Montana State University researcher shows that changes in the types of vegetation covering an area play a major role in determining how often that area is burned by fires and could even counteract the effects of changes in temperature and moisture.

In the study, MSU earth sciences post-doctoral researcher Philip Higuera and his colleagues show that the risk of wildfires can be either reduced or increased by changes in the distribution and abundance of plants. The study would be published in the recent issue of the journal Ecological Monographs.

"Climate affects vegetation, vegetation affects fire and both fire and vegetation respond to climate change," Higuera said. "Our work emphasizes the need to consider the multiple drivers of fire regimes when we anticipate how they will respond to climate change".

Higuera and his colleagues studied fire history in northern Alaska by analyzing sediments at the bottom of lakes, some dating as far back as 15,000 years. In the samples from the lakes, the scientists measured the abundance of different preserved plant parts, such as pollen, to determine what types of vegetation dominated the region in the past. Like rings in a tree, different sediment layers represent different times in the past......... Posted by: Tyler      Read more         Source

April 20, 2009, 9:59 PM CT

Is it going to rain today?

If Mark Twain were alive today he might rephrase his frequently cited observation about everyone talking about the weather but not doing anything about it to say, "Everyone reads or watches weather forecasts, but a number of people don't understand them."

He'd do that because new research indicates that only about half the population knows what a forecast means when it predicts a 20 percent chance of rain, as per scientists at the University of Washington.

Writing in the Bulletin of the American Meteorological Society, the scientists said the confusion comes because people don't understand what the 20 percent chance of rain actually refers to. A number of people think it means that it will rain over 20 percent of the area covered by the forecast or for 20 percent of the time period covered by the forecast, said Susan Joslyn, a UW cognitive psychology expert and senior lecturer.

"When a forecast says there is 20 percent chance of rain tomorrow it actually means it will rain on 20 percent of the days with exactly the same atmospheric conditions," she said. "With the exception of the probability of precipitation, most weather forecasts report a single value such as the high temperature will be 53 degrees. This is deterministic because it implies that forecasters are sure the high temperature will be 53 degrees. But forecasting is probabilistic and 53 degrees is in the middle of the range of possible temperatures, say 49 to 56 degrees."........ Posted by: Tyler      Read more         Source

April 20, 2009, 9:51 PM CT

Cuts in Greenhouse Gas Emissions Would Save Arctic Ice

The threat of global warming can still be greatly diminished if nations cut emissions of heat-trapping greenhouse gases by 70 percent this century, as per a new analysis. While global temperatures would rise, the most dangerous potential aspects of climate change, including massive losses of Arctic sea ice and permafrost and significant sea level rise, could be partially avoided.

The study, led by researchers at the National Center for Atmospheric Research (NCAR), will be published next week in Geophysical Research Letters. It was funded by the Department of Energy and the National Science Foundation, NCAR's sponsor.

"This research indicates that we can no longer avoid significant warming during this century," says NCAR scientist Warren Washington, the main author. "But if the world were to implement this level of emission cuts, we could stabilize the threat of climate change and avoid catastrophe".

Average global temperatures have warmed by close to 1 degree Celsius (almost 1.8 degrees Fahrenheit) since the pre-industrial era. Much of the warming is due to human-produced emissions of greenhouse gases, predominantly carbon dioxide. This heat-trapping gas has increased from a pre-industrial level of about 284 parts per million (ppm) in the atmosphere to more than 380 ppm today......... Posted by: Tyler      Read more         Source

April 20, 2009, 9:40 PM CT

West African Droughts are the Norm

Listen to an audio file of Timothy Shanahan, Jonathan Overpeck and Paul Filmer discussing the findings with reporters.

A newly released study of lake sediments in Ghana suggests that severe droughts lasting several decades, even centuries, were the norm in West Africa over the past 3,000 years.

The earlier dry spells dwarfed the well-documented drought that plagued West Africa in the late-20th century, and as the planet warms, the study's authors believe the region's rainfall patterns will have an even greater impact.

The team of georesearchers and climate scientists, led by Jonathan Overpeck of the University of Arizona and his former doctoral student, main author Timothy Shanahan, who is now at the University of Texas (UT) at Austin, announced their findings in the April 17, 2009, issue of Science.

Because of close agreement amongst several data sets, the researchers believe the droughts are driven in part by circulation of the ocean and atmosphere in and above the Atlantic--and possibly beyond. If climate models for such circulation patterns hold true, the study suggests global warming could create conditions that favor extreme droughts.

"Clearly, much of West Africa is already on the edge of sustainability," says Overpeck, "and the situation could become much more dire in the future with increased global warming"......... Posted by: Tyler      Read more         Source

April 13, 2009, 1:34 PM CT

Mathematics of climate change

University of Utah mathematician Ken Golden went to the Eastern Weddell Sea for the Antarctic Zone Flux Experiment. The sea's surface is normally covered with sea ice, the complex composite material that results when sea water is frozen. During a powerful winter storm, Golden observed liquid sea water welling up and flooding the sea ice surface, producing a slushy mixture of sea water and snow that freezes into snow-ice. With his mathematician's eyes he observed this phenomenon and said to himself: "That's percolation!".

Golden is an expert in mathematical models of percolation, a physical process in which a fluid moves and filters through a porous solid. Soon after the 1994 trip he started trying to understand how the mathematics of percolation could describe aspects of the formation and behavior of sea ice. His results appeared in a landmark paper in Science in 1998, written with co-authors S. F. Ackley and V. I. Lytle. Ever since then, Golden has been a leader in the international effort to model polar climate dynamics and has brought a new level of rigor and precision to this area of research.

Golden describes the mathematics he and collaborators have developed in "Climate Change and the Mathematics of Transport in Sea Ice", which will appear this month in the Notices of the American Mathematical Society. His article marks Mathematics Awareness Month, celebrated each year in April. For 2009, the theme of Mathematics Awareness Month is "Mathematics and Climate". Golden is serving as Chair of the Mathematics Awareness Month Committee this year......... Posted by: Tyler      Read more         Source

April 12, 2009, 7:16 AM CT

How do they spread?

Propagation of earthquake waves within the Earth is not uniform. Experiments indicate that the velocity of shear waves (s-waves) in Earth's lower mantle between 660 and 2900 km depth is strongly dependent on the orientation of ferropericlase. In the latest issue of "Science" (Vol. 325, 10.04.2009), scientists from the German Research Center for Geosciences GFZ, the Karlsruhe Institute of Technology, the University of Bayreuth, and Arizona State University report unexpected properties of ferropericlase, which is presumably the second most abundant mineral of the lower mantle.

"The dependence of wave velocity on direction increases significantly at a pressure of about 50 Giga-Pascal, corresponding to approximately 1300 km depth. This is caused by a change in electronic arrangement of the iron ions in ferropericlase" explains Hauke Marquardt from GFZ. In addition, flow in the lower mantle results in a preferred mineral orientation; this causes the detectable non-uniform propagation of earthquake waves. This flow is the driving force of tectonic plate movements, formation of mountains, earthquakes, and volcanic activities and therefore, strongly affects our life on Earth's surface.

Because the deep interior of our planet is not accessible to direct observations, the scientists simulate the conditions of Earth's interior by generating the extreme pressures in their laboratory. Diamond anvil cells are used at GFZ to perform the high-pressure experiments, which are complemented by X-ray diffraction experiments at "Diamond Light Source" in Didcot, UK......... Posted by: Tyler      Read more         Source

April 6, 2009, 10:12 PM CT

Arctic literally on thin ice

The latest data from NASA and the University of Colorado at Boulder's National Snow and Ice Data Center show the continuation of a decade-long trend of shrinking sea ice extent in the Arctic, including new evidence for thinning ice as well.

The researchers, who have been tracking Arctic sea ice cover with satellites since 1979, observed that the winter of 2008-09 was the fifth lowest maximum ice extent on record. The six lowest maximum events in the satellite record have all occurred in the past six years, as per CU-Boulder researcher Walt Meier of NSIDC.

The new measurements by CU-Boulder's NSIDC show the maximum sea ice extent for 2008-09 reached on Feb. 28 was 5.85 million square miles, which is 278,000 square miles below the average extent for 1979 to 2000, an area slightly larger than the state of Texas, said Meier.

In addition, a team of CU-Boulder scientists led by Research Associate Charles Fowler of the Colorado Center for Astrodynamics Research, or CCAR, has observed that younger, thinner ice has replaced older, thicker ice as the dominant type over the past five years, making it more prone to summer melt.

"Ice extent is an important measure of the health of the Arctic, but it only gives us a two dimensional view of the ice cover," said Meier. "Thickness is important, particularly in the winter, because it is the best overall indicator of the health of the ice cover. As the ice cover in the Arctic grows thinner, it becomes more vulnerable to summer melt"......... Posted by: Tyler      Read more         Source

April 2, 2009, 10:17 PM CT

Ice-Free Arctic Summers

Summers in the Arctic appears to be ice-free in as few as 30 years, not at the end of the century as previously expected. The updated forecast is the result of a new analysis of computer models coupled with the most recent summer ice measurements.

"The Arctic is changing faster than anticipated," said James Overland, an oceanographer at NOAA's Pacific Marine Environmental Laboratory and co-author of the study, which will appear April 3 in Geophysical Research Letters. "It's a combination of natural variability, along with warmer air and sea conditions caused by increased greenhouse gases".

Overland and his co-author, Muyin Wang, a University of Washington research scientist with the Joint Institute for the Study of the Atmosphere and Ocean in Seattle, analyzed projections from six computer models, including three with sophisticated sea ice physics capabilities. That data was then combined with observations of summer sea ice loss in 2007 and 2008.

The area covered by summer sea ice is expected to decline from its current 4.6 million square kilometers (about 2.8 million square miles) to about 1 million square kilometers (about 620,000 square miles) - a loss approximately four-fifths the size of the continental U.S. Much of the sea ice would remain in the area north of Canada and Greenland and decrease between Alaska and Russia in the Pacific Arctic......... Posted by: Tyler      Read more         Source

April 2, 2009, 5:23 AM CT

Effects of climate change on infectious diseases

Recent research has predicted that climate change may expand the scope of human infectious diseases. A new review, however, argues that climate change may have a negligible effect on pathogens or even reduce their ranges. The paper has sparked debate in the ecological community.

In a forum in the recent issue of Ecology, Kevin Lafferty of the U.S. Geological Survey's Western Ecological Research Center suggests that instead of a net expansion in the global range of diseases, climate change may cause poleward range shifts in the areas suitable for diseases as higher latitudes become warmer and regions near the equator become too hot.

The newly suitable areas for diseases will tend to be in more affluent regions where medicines are in widespread use and can more readily combat the diseases, Lafferty says. He cites model estimations that the most dangerous kind of malaria will gain 23 million human hosts outside of its current range by the year 2050, but will lose 25 million in its current range.

"The dramatic contraction of malaria during a century of warming suggests that economic forces might be just as important as climate in determining pathogen ranges," Lafferty says.

Mercedes Pascual of the University of Michigan sees the situation very differently. Pascual is the main author of one of five Forum papers published in response to Lafferty. Eventhough she agrees that disease expansion in some areas could be accompanied by retraction in others, she emphasizes that disease range does not always correlate with the number of humans infected. In regions of Africa and South America, for example, humans have historically settled in high latitudes and altitudes. If climate change makes these areas more fit for mosquito breeding and for pathogen development, she writes, then many infections could expand. She notes that researchers are already seeing evidence of this pattern......... Posted by: Tyler      Read more         Source

Thu, 02 Apr 2009 03:33:47 GMT

Go Green with Lucky Magazine and Almay

Our friends at Lucky Magazine have a wonderful offer for you which ALSO helps the environment (win-win!).

Please visit http://www.luckylookout.com/almay to learn more about Almay"s new Almay pure blends products - and for your chance to win a Lucky reusable tote. Almay and Lucky Magazine will plant a tree in your honor for visiting too! Posted by: Palacinka Beauty      Read more     Source

March 31, 2009, 2:52 PM CT

Ozone depletion from rocket launching

The global market for rocket launches may require more stringent regulation in order to prevent significant damage to Earth's stratospheric ozone layer in the decades to come, as per a newly released study by scientists in California and Colorado.

Future ozone losses from unregulated rocket launches will eventually exceed ozone losses due to chlorofluorocarbons, or CFCs, which stimulated the 1987 Montreal Protocol banning ozone-depleting chemicals, said Martin Ross, chief study author from The Aerospace Corporation in Los Angeles. The study, which includes the University of Colorado at Boulder and Embry-Riddle Aeronautical University, provides a market analysis for estimating future ozone layer depletion based on the expected growth of the space industry and known impacts of rocket launches.

"As the rocket launch market grows, so will ozone-destroying rocket emissions," said Professor Darin Toohey of CU-Boulder's atmospheric and oceanic sciences department. "If left unregulated, rocket launches by the year 2050 could result in more ozone destruction than was ever realized by CFCs".

A paper on the subject by Ross and Manfred Peinemann of The Aerospace Corporation, CU-Boulder's Toohey and Embry-Riddle Aeronautical University's Patrick Ross appeared online in March in the journal Astropolitics........ Posted by: Tyler      Read more         Source

March 31, 2009, 5:20 AM CT

Heat Transport In The Earth's Crust

Putting a new spin on an old technique, Anne M. Hofmeister, Ph.D., research professor of earth and planetary sciences in Arts & Sciences at Washington University in St. Louis, has revolutionized scientists' understanding of heat transport in the Earth's crust, the outermost solid shell of our planet.

Temperature is an important driver of a number of geological processes, including the generation of magmas (molten rocks) in the deepest parts of the Earth's crust, about 30 to 40 kilometers below the surface. Yet, until recently, temperatures deep inside the Earth's crust were uncertain, mainly because of difficulties linked to measuring thermal conductivity, or how much heat is flowing through the rocks that compose the crust.

In conventional methods of measuring thermal conductivity, measurement errors arise as the temperature of a rock nears its melting point. At such high temperatures, heat is not just transported from atom to atom by vibrations, but also by radiation (light). Since conventional methods cannot separate heat flow carried by vibrations from that linked to radiation, most measurements of how efficiently rocks transport heat at high temperatures have been overestimated. Because of this experimental uncertainty, researchers have assumed rock conductivity to be constant throughout the crust in order to make advances in models describing Earth's geological behavior......... Posted by: Tyler      Read more         Source

March 25, 2009, 9:43 PM CT

Key to understanding volcanic plumes

A 200-year-old report by a sea captain and photographs of the 2008 eruption of Mount Chaiten are helping researchers better understand strong volcanic plumes.

In a paper published this week in the journal Nature, the researchers show that the spontaneous formation of a "volcanic mesocyclone"--a rotating, column-shaped vortex--causes the volcanic plume to rotate on its axis.

The rotation, in turn, triggers a sheath of lightning and creates waterspouts or dust devils. The origins of these volcanic phenomena were previously unexplained.

"These results solve a long-standing mystery about the relationship between volcanic plumes and associated tornadoes, waterspouts and lightning, showing for the first time that rotation of a volcanic plume appears to be the primary cause of these effects," said Sonia Esperanca, program director in the National Science Foundation's (NSF) geosciences directorate.

The research is supported by NSF, via three directorates: geosciences; mathematical and physical sciences; and engineering.

"Rotation is an essential element of a strong volcanic plume," said Pinaki Chakraborty, a computational scientist and engineer at the University of Illinois and the paper's main author. "By taking into account the rotation, we can better predict the effects of volcanic eruptions"......... Posted by: Tyler      Read more         Source

March 24, 2009, 6:15 AM CT

Was Triceratops a social animal?

Until now, Triceratops was believed to be unusual among its ceratopsid relatives. While a number of ceratopsidsa common group of herbivorous dinosaurs that lived toward the end of the Cretaceoushave been found in enormous bonebed deposits of multiple individuals, all known Triceratops (over 50 in total) fossils have been solitary individuals. But a new discovery of a jumble of at least three juveniles the badlands of the north-central United States suggests that the three-horned dinosaurs were not only social animals, but may have exhibited unique gregarious groupings of juveniles.

"This is very thrilling," says Stephen Brusatte, an affiliate of the American Museum of Natural History and a doctoral student at Columbia University. "We can say something about how these dinosaurs lived. Interestingly, what we've found seems to be a larger pattern among a number of dinosaurs that juveniles lived and traveled together in groups".

In 2005, Brusatte and his colleagues found and excavated a site that contained multiple Triceratops juveniles in 66-million-year-old rocks in southeastern Montana. The geological evidence suggests that at least three juveniles were deposited at the same time by a localized flood, and this suggests that they were probably living together when disaster struck. This find indicates that Triceratops juveniles congregated in small herds, a social behavior increasingly identified in other dinosaur groups, such as Psittacosaurus, a small cousin of Triceratops that lived in Asia......... Posted by: Tyler      Read more         Source

March 16, 2009, 7:28 PM CT

Poor nations pay the price for global warming

A rising tide is said to lift all boats. Rising global temperatures, however, may lead to increased disparities between rich and poor countries, as per a recent MIT economic analysis of the impact of climate change on growth.

After examining worldwide climate and economic data from 1950 to 2003, Benjamin A. Olken, associate professor in the Department of Economics, concludes that a 1 degree Celsius rise in temperature in a given year reduces economic growth by an average of 1.1 percentage points in the world's poor countries but has no measurable effect in rich countries.

Olken says his research suggests higher temperatures will be disproportionately bad for the economic growth of poor countries in comparison to rich countries.

The precise reasons why higher temperatures lower economic output are likely to be complex, but Olken's results suggest the importance of temperature's impact on agricultural output. His data also provide evidence for a relationship between temperature and industrial output, investment, research productivity and political stability.

"The potential impacts of an increase in temperature on poor countries are much larger than existing estimates have suggested," Olken says. "Eventhough historical estimates don't necessarily predict the future, our results suggest that one should be especially attentive to the potential impact of climate change on poorer countries"......... Posted by: Tyler      Read more         Source

February 27, 2009, 6:14 AM CT

Biodegradable mulch films on the horizon

In 1999, more than 30 million acres of agricultural land worldwide were covered with plastic mulch, and those numbers have been increasing significantly since then. With the recent trend toward "going green", scientists are seeking environmentally friendlier alternatives to conventional plastic mulch.

Plastic mulch can provide earlier crop maturity, higher yields, increased quality, improved disease and insect resistance, and more efficient water and fertilizer use, but carries a high cost financially and environmentally when it comes to removing the estimated one million tons of mulch film used internationally each year.

Mathieu Ngouajio, of the Department of Horticulture at Michigan State University, led a study comparing black and white biodegradable mulch films in two thicknesses to traditional plastic mulch in the production of tomato. The results of the study were reported in the American Society for Horticultural Science journal HortTechnology

The lowest soil temperatures were identified with the white films, which is also linked to the white film's higher rate of degradation. Breakdown of white mulch occurred early and exposed the bed for weed growth, creating competition for nutrients between weeds and tomato. As the weeds grew, they tore the mulch, leading to further degradation. Furthermore, the weeds hosted a large insect population that reduced the quality of the tomato......... Posted by: Tyler      Read more         Source